ESD reliability issues in microelectromechanical systems (MEMS): A case study on micromirrors

For the first time a study of electrostatically actuated torsional micromirrors under ESD stress is presented. Together with on-wafer ESD measurements their electrical and mechanical behavior under ESD stress is explained. HBM and MM measurements have been performed and their relevance in calculating the ESD failure level of the micromirrors is compared and discussed in detail. It is demonstrated that these optical MEMS devices have a high sensitivity to ESD and that they need ESD protection.